Outboard Transom Clamp Bolts Seized

[Bustlebomb]

Hi all,

I have a 6hp Nissan outboard for my dinghy. Evidently, when I last used it, I failed to clean/lubricate the clamp bolts (I know, bonehead move). Now they are well and truly stuck, I'm assuming corrosion. What I've done:

- Liquid Wrench/penetrating oil (repeatedly over the past week)
- I drilled one hole sideways into the bracket (to allow oil to penetrate the threaded portion) and soaked 48 hours in a mixture of 50/50 acetone and ATF
-I applied some heat although I am leery about using too much heat as I don't want to damage the aluminum

I'm stuck, or at least my clamp bolts are.

Does anyone have any suggestions to fix this?

Thanks,

 

[alormaria]

Soak in PB Blaster. Light tapping with a brass hammer to shock and work the PB into the threads.



Do this everyday for a week.



Patience.

 

[Swfla]

PB Blaster is superior to liquid wrench. Heat followed with cold for rapid expansion contraction may break the corrosion too. Canned air gets quite cold. Otherwise, cut off ends of clamps and drill out. Sorry.

 

[psneeld]

According to one test I read, the 50/50 ATF Acetone mix beat all store bought penetrating liquids.

One possibility would be to get rid of the handles on the ends of the bolts...grind the bolts to accept a socket on an impact wrench. Depends on how desperate you get.

 

[Dougcole]

You may have to cut the “handles” off anyway as the will likely break under a lot of torque. Then maybe you can get a pipe wrench on them with a long convincer pipe slipped over the handle?

 

[psneeld]

You may have to cut the “handles” off anyway as the will likely break under a lot of torque. Then maybe you can get a pipe wrench on them with a long convincer pipe slipped over the handle?

I too have found long handle cheaters with gentle pressure do work wonders....even break bolts loose when the short handle version tends to break bolts.

I would still try impact as it seems to break corrosion rather than twist metal.

 

[Comodave]

Use a 1/2” impact driver not the little 1/4” impact driver. Go easy with it and let the vibration do the work. I also use PB Blaster. Do a few quick shots with the impact and wait for the PB to work. Wait and repeat multiple times. Don’t go full throttle on the impact at first.

 

[O C Diver]

After soaking with penetrating oil, put a wrench with a cheater bar on it, apply pressure and have someone else
tap the end of the screw with a punch and hammer. Same principle as using a propeller puller and tapping the hub or end of the shaft with a hammer to break the taper loose.

Ted

 

[Ski in NC]

Heat/penetrant/alternate motion. Can use two hammers, one heavier one as an anvil against the al body, other lighter one to tap on the al to the side of the the threaded body. Repeat as necessary. You will get it.

 

[RT Firefly]

 

[Sidclark]

If you're using a propane torch for heat, then don't worry about damaging the aluminum. A propane torch will not be able to get it hot enough to damage. If you're using oxy-acetylene, then yes, you have to be careful. Even with a propane torch the heat can travel and damage the fiberglass transom. I would wrap wet rags around the area where the bolts meet the transom. So, penetrant and heat, rinse and repeat. Hopefully the threads in the bracket won't get galled up.

 

[Bustlebomb]

Thanks for the input. Sidclark, I'm lucky - the motor is off the dinghy and on a stand in my garage.

I soaked it with PB Blaster last night and banged on it with a hammer. I'll continue that today and I'll try these other suggestions and report back. Really hope I can get them loose....

 

[Bustlebomb]

Success! Me- 1, corrosion - 0!! I was able to get them free and I’m back in business. Thanks for all the input.

If you were wondering, heat, PB Blaster, banging on it with a hammer (actually, two hammers), and patience, lots and lots of patience.

 

[Swfla]

Great news and perseverance.

 

[Comodave]

Good for you!!!